Polygon mirror drive motor and laser mirror radiation device

Abstract

The invention discloses a polygonal mirror driving motor and a laser mirror irradiation device equipped with the polygonal mirror driving motor, which can prevent the deviation of the synchronization signal itself from reducing the detection accuracy caused by the installation error of various components, and then can accurately detect and control from A signal for the emission timing of the laser beam emitted from the laser light source. It is characterized by setting a frequency generating magnetizing part (FG magnet 7), a frequency generating pattern (FG pattern 6), and a frequency dividing circuit 24, and using the frequency dividing circuit 24 to generate frequency when the frequency generating magnetizing part (FG magnet 7) rotates The signal detected in the pattern (FG pattern 6 ) is frequency-divided into the number of mirror surfaces of the polygon mirror 14 and output.

Description

technical field [0001] The present invention relates to a polygon mirror drive motor that rotates and periodically deflects a laser beam emitted from a laser light source, and a laser mirror irradiation device equipped with the polygon mirror drive motor, and particularly relates to the control of the emission timing of the laser beam emitted from a laser light source . Background technique [0002] Generally, in laser printers, copiers, workshop measurement devices, etc., laser mirror irradiation devices with polygonal mirrors (rotating polygonal mirrors) are used in various places. For example, in the laser printer shown in the schematic diagram of FIG. 10 , the output beam of the semiconductor laser is parallelized by the imaging lens 102 and then enters the polygon mirror 104 that is rotated by a polygon mirror driving motor. Then, the reflected light from the polygon mirror 104 passes through the fθ lens, forms an image on the light spot on the photosensitive drum 106,...

AI Technical Summary

Problems solved by technology

[0011] However, there is a problem that the above-mentioned synchronization signal is easily affected by an installation error when installing the sensor 107.

[0012] That is to say, there is a problem that although the synchronous signal is detected by the sensor 107, when the sensor 107 is installed in the housing, there is a problem that it is not connected with the motor drive magnet that is arranged on the peripheral surface of the polygon mirror drive motor 103. In the positional relationship, when there is a deviation from the predetermined position, for example, when a synchronous signal with a different pulse width is detected, the synchronous signal itself will deviate, reducing the detection accuracy

[0013] In addition, the reduction of the detection accuracy is caused not only by installation errors when installing the sensor 107, but also by various errors, such as installation errors of the housing where the sensor 107 is installed, and installation errors when the motor drive magnet is fixedly installed. , the installation error of each component, the relative error between the mirror and the magnet, etc.

[0014] In this way, in the conventional polygon mirror driving motor in which the synchronization signal is individually detected by the sensor 107, the above-mentioned error causes a decrease in detection accuracy, and as a result, the laser irradiation interval of each reflection surface of the polygon mirror varies.

When the laser irradiation interval deviates, for example, if the laser mirror irradiation device is a laser printer, it becomes difficult to print correctly without confusion, and when the laser mirror irradiation device is a workshop measurement device, accurate measurement becomes difficulty

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